PHY sub-channel processing

ABSTRACT

Physical layer (PHY) sub-channel processing. A soft symbol decision stream is arranged into a number of sub-channels to reduce substantially the processing performed within a communication receiver on data that is not intended for that communication receiver. In other embodiments, a predetermined approach is employed to arrange the soft symbol decision stream into one or more frames; each frame may have one or more soft symbol blocks; and each soft symbol block may have one or more symbols. Each of the soft symbol blocks, within a frame, may be assigned to a sub-channel. Only the soft symbol blocks that contain information destined for the communication receiver need be decoded. Only the sub-channel that includes these soft symbol blocks, destined for this communication receiver, need be decoded. The soft symbol blocks not within the sub-channel may be discarded thereby recovering some of the processing capabilities of the communication receiver.

CROSS REFERENCE TO RELATED PATENTS/PATENT APPLICATIONS

Continuation priority claim, 35 U.S.C. §120

The present U.S. Utility Patent Application claims priority pursuant to35 U.S.C. § 120, as a continuation, to the following U.S. Utility PatentApplication which is hereby incorporated herein by reference in itsentirety and made part of the present U.S. Utility Patent Applicationfor all purposes:

1. U.S. Utility application Ser. No. 10/420,089, entitled “PHYsub-channel processing,” (Attorney Docket No. BP2432), filed Apr. 22,2003, pending, which claims priority pursuant to 35 U.S.C. § 119(e) tothe following U.S. Provisional Patent Application which is herebyincorporated herein by reference in its entirety and made part of thepresent U.S. Utility patent application for all purposes:

a. U.S. Provisional Application Ser. No. 60/388,987, “PHY sub-channelprocessing,” (Attorney Docket No. BP2432), filed Jun. 14, 2002.

BACKGROUND OF THE INVENTION

1. Technical Field of the Invention

The invention relates generally to communication systems; and, moreparticularly, it relates to receiver processing within communicationsystems.

2. Description of Related Art

Data communication systems have been under continual development formany years. There is oftentimes a design motivation to increase thespeed of processing, at both ends of a communication channel, to be asfast as possible in an effort to maximize throughput within the system.In a typical communication receiver application that receives a multipleaccess signal, such as a broadcast signal, there is a lot of receiveddata that is processed and never used. As an example, in a broadcastsystem, a communication receiver will typically decode all of the dataof a received channel before selecting and extracting the dataspecifically appropriate for that communication receiver.

A typical such communication receiver may often be described as follows:a signal is received from a communication channel. A demodulator willtake this received signal and calculate soft symbol decisions ofreceived symbols of that received signal. These soft symbol decisions,in a stream format, are then passed to a decoder that generates harddecisions from those soft symbol decisions that are then output from thedecoder in a bit stream format. This bit stream may then be passed ontosome higher level applications that will then determine which portionsof the bit stream are destined for this communication receiver. Thoseportions of the bit stream that are not intended for this communicationreceiver may then be discarded. In this situation, a lot of processingis performed on portions the received signal that are never used. Thisprior art approach is inherently consumptive of the processingcapabilities of the communication receiver, in that, a great deal ofprocessing is performed on data that is received, but not necessarilyintended to be used, by the communication receiver.

Therefore, there exists a need in the art for a more efficient way toperform processing of received data that will be less consumptive of thecommunication receiver's processing capabilities without sufferingdegradation in performance.

BRIEF SUMMARY OF THE INVENTION

The present invention is directed to apparatus and methods of operationthat are further described in the following Brief Description of theSeveral Views of the Drawings, the Detailed Description of theInvention, and the claims. Other features and advantages of the presentinvention will become apparent from the following detailed descriptionof the invention made with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a system diagram illustrating an embodiment of a satellitecommunication system that is built according to the present invention.

FIG. 2 is a system diagram illustrating an embodiment of a highdefinition television (HDTV) communication system that is builtaccording to the present invention.

FIG. 3 is a system diagram illustrating an embodiment of a cellularcommunication system that is built according to the present invention.

FIG. 4 is a system diagram illustrating another embodiment of a cellularcommunication system that is built according to the present invention.

FIG. 5 is a system diagram illustrating an embodiment of a microwavecommunication system that is built according to the present invention.

FIG. 6 is a system diagram illustrating an embodiment of apoint-to-point radio communication system that is built according to thepresent invention.

FIG. 7 is a system diagram illustrating an embodiment of auni-directional communication system that is built according to thepresent invention.

FIG. 8 is a system diagram illustrating an embodiment of abi-directional communication system that is built according to thepresent invention.

FIG. 9 is a system diagram illustrating an embodiment of a one to manycommunication system that is built according to the present invention.

FIG. 10 is a system diagram illustrating an embodiment of a satellitereceiver set-top box receiver system that is built according to thepresent invention.

FIG. 11 is a diagram illustrating an embodiment of physical layer (PHY)sub-channel processing functionality that is supported according to thepresent invention.

FIG. 12 is a diagram illustrating an embodiment of a receiver arrangedto support PHY sub-channel processing according to the presentinvention.

FIG. 13 is a diagram illustrating an embodiment of PHY sub-channelprocessing that is performed according to the present invention.

FIG. 14 is a diagram illustrating another embodiment of PHY sub-channelprocessing that is performed according to the present invention.

FIG. 15 is a diagram illustrating an embodiment of information codedwithin soft symbol blocks of a sub-channel and programmable look aheadto subsequent frames according to the invention.

FIG. 16 is a diagram illustrating an embodiment of information codedwithin soft symbol blocks of a sub-channel according to the invention.

FIG. 17 is a diagram illustrating an embodiment of code rates that areemployed to decode soft symbol blocks of sub-channels according to theinvention.

FIG. 18 is a diagram illustrating an embodiment of code rates employedto decode soft symbol blocks according to the invention.

FIG. 19 is a constellation diagram illustrating an embodiment ofmodulations (constellations and mappings) for code rates 1 and n shownin FIG. 18.

FIG. 20 is a diagram illustrating an embodiment of PHY sub-channelselection of a video broadcast signal according to the invention.

FIG. 21 and FIG. 22 are operational flow diagrams illustratingembodiments of sub-channel processing methods that are performedaccording to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1-9 illustrate a number of communication system contextembodiments where certain aspects of the invention may be implemented.

FIG. 1 is a system diagram illustrating an embodiment of a satellitecommunication system 100 that is built according to the presentinvention. A satellite transmitter 110 is operable to supportsub-channel encoding. This sub-channel encoding may also be performedwhen doing training field encoding. In other embodiments, a trainingfield is transmitted from the satellite transmitter 110 withoutundergoing any encoding. The sub-channel encoding may be performed usingany one of several possible embodiments that are described herein. Thesub-channel encoding encodes data that is to be transmitted by thesatellite transmitter 110. The satellite transmitter 110 iscommunicatively coupled to a satellite dish 115 that is operable tocommunicate with a satellite 150. The satellite transmitter 110 may alsobe communicatively coupled to a wired network. This wired network mayinclude any number of networks including the Internet, proprietarynetworks, and other wired networks. The satellite transmitter 110employs the satellite dish 115 to communicate to the satellite 150 via awireless communication channel. The satellite 150 is able to communicatewith one or more satellite receivers, shown as satellite receiver(s) 120(each having a satellite dish 125).

Each of the one or more satellite receiver(s) 120 is operable to supportphysical layer (PHY) sub-channel processing according to the invention.Each of the satellite receiver(s) 120 may be viewed as corresponding toa subscriber of the services provided by the satellite transmitter 110.Each of the satellite receiver(s) 120 may also be communicativelycoupled to a display, shown as display(s) 127. Various and furtherdetails will be provided below regarding the various embodiments bywhich PHY sub-channel processing may be performed according to theinvention.

Here, the communication to and from the satellite 150 may cooperativelybe viewed as being a wireless communication channel, or each of thecommunication to and from the satellite 150 may be viewed as being twodistinct wireless communication channels.

For example, the wireless communication “channel” may be viewed as notincluding multiple wireless hops in one embodiment. In otherembodiments, the satellite 150 receives a signal received from thesatellite transmitter 110 (via its satellite dish 115), amplifies it,and relays it to one or more of the satellite receiver(s) 120 (via itsrespective satellite dish 125); any one of the satellite receiver(s) 120may also be implemented using terrestrial receivers such as satellitereceivers, satellite based telephones, and satellite based Internetreceivers, among other receiver types. In the case where the satellite150 receives a signal received from the satellite transmitter 110 (viaits satellite dish 115), amplifies it, and relays it, the satellite 150may be viewed as being a “transponder.” In addition, other satellitesmay exist that perform both receiver and transmitter operations incooperation with the satellite 150 up in space. In this case, each legof an up-down transmission via the wireless communication channel wouldbe considered separately.

In whichever embodiment, the satellite 150 communicates with one or moreof the satellite receiver(s) 120. One or more of the satellitereceiver(s) 120 may be viewed as being a mobile unit in certainembodiments (employing a local antenna); alternatively, one or more ofthe satellite receiver(s) 120 may be viewed as being a satellite earthstation that may be communicatively coupled to a wired network in asimilar manner in which the satellite transmitter 110 may also becommunicatively coupled to a wired network. The FIG. 1 shows one of themany embodiments where PHY sub-channel processing may be performedaccording to any one or more of the various embodiments of theinvention. It is noted that this PHY sub-channel processing includesboth sub-channel encoding at a transmitter end of a communicationchannel, as well as PHY sub-channel processing at the receiver end ofthe communication channel.

FIG. 2 is a system diagram illustrating an embodiment of a highdefinition television (HDTV) communication system 200 that is builtaccording to the present invention. An HDTV transmitter 220 iscommunicatively coupled to a tower 221. The HDTV transmitter 220, usingits tower 221, transmits a signal to a local tower dish 212 via awireless communication channel. The local tower dish 212 communicativelycouples to an HDTV set top box receiver 210 via a coaxial cable. TheHDTV set top box receiver 210 includes the functionality to receive thewireless transmitted signal that has been received by the local towerdish 212; this may include any transformation and/or down-converting aswell to accommodate any up-converting that may have been performedbefore and during transmission of the signal from the HDTV transmitter220 and its tower 221.

The HDTV set top box receiver 210 is also communicatively coupled to anHDTV display 230 that is able to display the demodulated and decodedwireless transmitted signals received by the HDTV set top box receiver210 and its local tower dish 212. The HDTV transmitter 220 (via itstower 221) transmits a signal directly to the local tower dish 412 viathe wireless communication channel in this embodiment. In alternativeembodiments, the HDTV transmitter 220 may first receive a signal from asatellite 250, using a satellite earth station 222 that iscommunicatively coupled to the HDTV transmitter 220, and then transmitthis received signal to the to the local tower dish 212 via the wirelesscommunication channel. In this situation, the HDTV transmitter 220operates as a relaying element to transfer a signal originally providedby the satellite 250 that is destined for the HDTV set top box receiver210. For example, another satellite earth station may first transmit asignal to the satellite 250 from another location, and the satellite 250may relay this signal to the satellite earth station 222 that iscommunicatively coupled to the HDTV transmitter 220. The HDTVtransmitter 220 performs receiver functionality and then transmits itsreceived signal to the local tower dish 212.

In even other embodiments, the HDTV transmitter 220 employs thesatellite earth station 222 to communicate to the satellite 250 via awireless communication channel. The satellite 250 is able to communicatewith a local satellite dish 213; the local satellite dish 213communicatively couples to the HDTV set top box receiver 210 via acoaxial cable. This path of transmission shows yet another communicationpath where the HDTV set top box receiver 210 may communicate with theHDTV transmitter 220.

In whichever embodiment and whichever signal path the HDTV transmitter220 employs to communicate with the HDTV set top box receiver 210, theHDTV set top box receiver 210 is operable to receive communicationtransmissions from the HDTV transmitter 220.

The HDTV transmitter 220 includes an embodiment of the sub-channelencoding as described above. This may also include training fieldencoding as well, as also mentioned above. The FIG. 2 shows yet anotherof the many embodiments where PHY sub-channel processing may beperformed according to any one or more of the various embodiments of theinvention. It is noted that this PHY sub-channel processing includesboth sub-channel encoding at a transmitter end of a communicationchannel, as well as PHY sub-channel processing at the receiver end ofthe communication channel.

FIG. 3 is a system diagram illustrating an embodiment of a cellularcommunication system 300 that is built according to the presentinvention. A mobile transmitter 310 includes a local antenna 315communicatively coupled thereto. The mobile transmitter 310 may be anynumber of types of transmitters including a cellular telephone, awireless pager unit, a mobile computer having transmit functionality, orany other type of mobile transmitter. The mobile transmitter 310transmits a signal, using its local antenna 315, to a receiving tower345 via a wireless communication channel. The receiving tower 345 iscommunicatively coupled to a base station receiver 340; the receivingtower 345 is operable to receive data transmission from the localantenna 315 of the mobile transmitter 310 that have been communicatedvia the wireless communication channel. The receiving tower 345communicatively couples the received signal to the base station receiver340.

The mobile transmitter 310 is operable to support sub-channel encoding.This sub-channel encoding may also be performed when doing trainingfield encoding. In other embodiments, a training field is transmittedfrom the mobile transmitter 310 without undergoing any encoding. Thesub-channel encoding may be performed using any one of several possibleembodiments that are described herein. The base station receiver 340 isoperable to support PHY sub-channel processing according any one of thevarious embodiments of the invention described herein.

The FIG. 3 shows yet another of the many embodiments where PHYsub-channel processing may be performed according to any one or more ofthe various embodiments of the invention. It is noted that this PHYsub-channel processing includes both sub-channel encoding at atransmitter end of a communication channel, as well as PHY sub-channelprocessing at the receiver end of the communication channel.

FIG. 4 is a system diagram illustrating another embodiment of a cellularcommunication system 400 that is built according to the presentinvention. From certain perspectives, the cellular communication system400 of the FIG. 4 may be viewed as being the reverse transmissionoperation of the cellular communication system 300 of the FIG. 3. A basestation transmitter 420 is communicatively coupled to a transmittingtower 425. The base station transmitter 420, using its transmittingtower 425, transmits a signal to a local antenna 435 via a wirelesscommunication channel. A mobile receiver 430 includes the local antenna435 communicatively coupled thereto. The local antenna 435 iscommunicatively coupled to a mobile receiver 430 so that the mobilereceiver 430 may receive transmission from the transmitting tower 435 ofthe base station transmitter 420 that have been communicated via thewireless communication channel. The local antenna 435 communicativelycouples the received signal to the mobile receiver 430. It is noted thatthe mobile receiver 430 may be any number of types of receiversincluding a cellular telephone, a wireless pager unit, a mobile computerhaving receive functionality, or any other type of mobile receiver.

The base station transmitter 420 is operable to support sub-channelencoding. This sub-channel encoding may also be performed when doingtraining field encoding. In other embodiments, a training field istransmitted from the base station transmitter 420 without undergoing anyencoding. The sub-channel encoding may be performed using any one ofseveral possible embodiments that are described herein. The mobilereceiver 430 is operable to support PHY sub-channel processing accordingany one of the various embodiments of the invention described herein.

The FIG. 4 shows yet another of the many embodiments where PHYsub-channel processing may be performed according to any one or more ofthe various embodiments of the invention. It is noted that this PHYsub-channel processing includes both sub-channel encoding at atransmitter end of a communication channel, as well as PHY sub-channelprocessing at the receiver end of the communication channel.

FIG. 5 is a system diagram illustrating an embodiment of a microwavecommunication system 500 that is built according to the presentinvention. A transmitter 510 is communicatively coupled to a microwavetower 515. The transmitter 510, using its microwave tower 515, transmitsa signal to a microwave tower 525 via a wireless communication channel.A receiver 520 is communicatively coupled to the microwave tower 525.The microwave tower 525 is able to receive transmissions from themicrowave tower 515 that have been communicated via the wirelesscommunication channel.

The transmitter 510 is operable to support sub-channel encoding. Thissub-channel encoding may also be performed when doing training fieldencoding. In other embodiments, a training field is transmitted from thetransmitter 510 without undergoing any encoding. The sub-channelencoding may be performed using any one of several possible embodimentsthat are described herein. The receiver 520 is operable to support PHYsub-channel processing according any one of the various embodiments ofthe invention described herein.

The FIG. 5 shows yet another of the many embodiments where PHYsub-channel processing may be performed according to any one or more ofthe various embodiments of the invention. It is noted that this PHYsub-channel processing includes both sub-channel encoding at atransmitter end of a communication channel, as well as PHY sub-channelprocessing at the receiver end of the communication channel.

FIG. 6 is a system diagram illustrating an embodiment of apoint-to-point radio communication system 600 that is built according tothe present invention. A mobile unit 610 includes a local antenna 615communicatively coupled thereto. The mobile unit 610, using its localantenna 615, transmits a signal to a local antenna 625 via a wirelesscommunication channel. A mobile unit 620 includes the local antenna 625communicatively coupled thereto. The mobile unit 620 may receivetransmissions from the mobile unit 610 that have been communicated viathe wireless communication channel.

The mobile unit 610 is operable to support sub-channel encoding. Thissub-channel encoding may also be performed when doing training fieldencoding. In other embodiments, a training field is transmitted from themobile unit 610 without undergoing any encoding. The sub-channelencoding may be performed using any one of several possible embodimentsthat are described herein. The mobile unit 620 is operable to supportPHY sub-channel processing according any one of the various embodimentsof the invention described herein.

It is also noted that the point-to-point radio communication system 600may also support bi-directional communication where each of the mobileunits 610 and 620 may transmit/receive communication from each other. Inthis case, each of the mobile units 610 and 620 is operable to supportboth

The FIG. 6 shows yet another of the many embodiments where PHYsub-channel processing may be performed according to any one or more ofthe various embodiments of the invention. It is noted that this PHYsub-channel processing includes both sub-channel encoding at atransmitter end of a communication channel, as well as PHY sub-channelprocessing at the receiver end of the communication channel.

FIG. 7 is a system diagram illustrating an embodiment of auni-directional communication system 700 that is built according to thepresent invention. A transmitter 710 communicates with a receiver 720via a uni-directional communication channel 799. The uni-directionalcommunication channel 799 may be a wireline (or wired) communicationchannel or a wireless communication channel without departing from thescope and spirit of the invention. The wired media by which theuni-directional communication channel 799 may be implemented are varied,including coaxial cable, fiber-optic cabling, and copper cabling, amongother types of “wiring.” Similarly, the wireless manners in which theuni-directional communication channel 799 may be implemented are alsovaried, including satellite communication, cellular communication,microwave communication, and radio communication, among other types ofwireless communication.

The transmitter 710 is operable to support sub-channel encoding. Thissub-channel encoding may also be performed when doing training fieldencoding. In other embodiments, a training field is transmitted from thetransmitter 710 without undergoing any encoding. The sub-channelencoding may be performed using any one of several possible embodimentsthat are described herein. The receiver 720 is operable to support PHYsub-channel processing according any one of the various embodiments ofthe invention described herein.

The FIG. 7 shows yet another of the many embodiments where PHYsub-channel processing may be performed according to any one or more ofthe various embodiments of the invention. It is noted that this PHYsub-channel processing includes both sub-channel encoding at atransmitter end of a communication channel, as well as PHY sub-channelprocessing at the receiver end of the communication channel.

FIG. 8 is a system diagram illustrating an embodiment of abi-directional communication system 800 that is built according to thepresent invention. A transceiver 841 and a transceiver 842 are able tocommunicate with one another via a bi-directional communication channel899. The bi-directional communication channel 899 may be a wireline (orwired) communication channel or a wireless communication channel withoutdeparting from the scope and spirit of the invention. The wired media bywhich the bi-directional communication channel 899 may be implementedare varied, including coaxial cable, fiber-optic cabling, and coppercabling, among other types of “wiring.” Similarly, the wireless mannersin which the bi-directional communication channel 899 may be implementedare varied, including satellite communication, cellular communication,microwave communication, and radio communication, among other types ofwireless communication.

The transceiver 841 is operable to support sub-channel encoding. Thissub-channel encoding may also be performed when doing training fieldencoding. In other embodiments, a training field is transmitted from thetransceiver 841 without undergoing any encoding. The sub-channelencoding may be performed using any one of several possible embodimentsthat are described herein. The transceiver 842 is operable to supportPHY sub-channel processing according any one of the various embodimentsof the invention described herein.

Similarly, to support the bi-directional functionality of the invention,the transceiver 842 is operable to support sub-channel encoding. Thissub-channel encoding may also be performed when doing training fieldencoding. In other embodiments, a training field is transmitted from thetransceiver 842 without undergoing any encoding. The sub-channelencoding may be performed using any one of several possible embodimentsthat are described herein. The transceiver 841 is also operable tosupport PHY sub-channel processing according any one of the variousembodiments of the invention described herein.

The FIG. 8 shows yet another of the many embodiments where PHYsub-channel processing may be performed according to any one or more ofthe various embodiments of the invention. It is noted that this PHYsub-channel processing includes both sub-channel encoding at atransmitter end of a communication channel, as well as PHY sub-channelprocessing at the receiver end of the communication channel. This PHYsub-channel processing may also be viewed as being performed to supportthe reverse communication across the bi-directional communicationchannel 899.

FIG. 9 is a system diagram illustrating an embodiment of a one to manycommunication system 900 that is built according to the presentinvention. From certain perspectives, this one to many communicationsystem 900 may be viewed as being a broadcast communication system. Atransmitter 910 is able to communicate, via broadcast in certainembodiments, with a number of receivers, shown as receiver(s) 1, 2, . .. , and 3 via a uni-directional communication channel 999. Each of thereceiver(s) 1, 2, . . . , and 3 may be viewed as being associated with asubscriber that receives services provided by the transmitter 910. Theuni-directional communication channel 999 may be a wireline (or wired)communication channel or a wireless communication channel withoutdeparting from the scope and spirit of the invention. The wired media bywhich the uni-directional communication channel 999 may be implementedare varied, including coaxial cable, fiber-optic cabling, and coppercabling, among other types of “wiring.” Similarly, the wireless mannersin which the uni-directional communication channel 999 may beimplemented are varied, including satellite communication, cellularcommunication, microwave communication, and radio communication, amongother types of wireless communication.

A distribution point 950 is employed within the one to manycommunication system 900 to provide the appropriate communication to thereceiver(s) 1, 2, . . . , and 3. In certain embodiments, the receivers(receivers) 1, 2, . . . , and 3) each receive the same communication andindividually discern which portion of the total communication isintended for themselves. The processing of this received information, beeach of the receiver(s) 1, 2, . . . , and 3, is substantially improvedand performed in a more efficient manner by employing the PHYsub-channel processing according to the invention.

The transmitter 910 is operable to support sub-channel encoding. Thissub-channel encoding may also be performed when doing training fieldencoding. In other embodiments, a training field is transmitted from thetransmitter 910 without undergoing any encoding. The sub-channelencoding may be performed using any one of several possible embodimentsthat are described herein. The receivers) 1, 2, . . . , and 3 are eachoperable to support PHY sub-channel processing according any one of thevarious embodiments of the invention described herein.

The FIG. 9 shows yet another of the many embodiments where PHYsub-channel processing may be performed according to any one or more ofthe various embodiments of the invention. It is noted that this PHYsub-channel processing includes both sub-channel encoding at atransmitter end of a communication channel, as well as PHY sub-channelprocessing at the receiver end of the communication channel.

FIG. 10 is a system diagram illustrating an embodiment of a satellitereceiver set-top box receiver system 1000 that is built according to thepresent invention. The satellite receiver set-top box system 1000includes an advanced modulation satellite receiver 1010 that isimplemented in an all digital architecture. The satellite receiverset-top box system 1000 includes a satellite tuner 1002 that receives asignal via the L-band. The satellite tuner 1002 extracts I,Q (in-phaseand quadrature) components from a signal received from the L-band andprovides them to the advanced modulation satellite receiver 1010. Theadvanced modulation satellite receiver 1010 is operable to support PHYsub-channel processing according to the invention. The advancedmodulation satellite receiver 1010 communicatively couples to an HDTVMPEG-2 (Motion Picture Expert Group) transport de-mux, audio/videodecoder and display engine 1020. Both the advanced modulation satellitereceiver 1010 and the HDTV MPEG-2 transport de-mux, audio/video decoderand display engine 1020 communicatively couple to a host centralprocessing unit (CPU) 1030. The HDTV MPEG-2 transport de-mux,audio/video decoder and display engine 1020 also communicatively couplesto a memory module 1032 and a conditional access functional block 1034.The HDTV MPEG-2 transport de-mux, audio/video decoder and display engine1020 provides HD video and audio output that may be provided to an HDTVdisplay.

The advanced modulation satellite receiver 1010 is a single-chip digitalsatellite receiver supporting PHY sub-channel processing according tothe invention. Several of the many embodiments of the variable code rateoperation are described in even more detail below. The advancedmodulation satellite receiver 1010 is operable to receive communicationprovided to it from a transmitter device according to the invention. Thecode rate may be viewed as being the ratio of the number of informationbits within a symbol over the total number of bits within a symbol.

FIG. 11 is a diagram illustrating an embodiment of physical layer (PHY)sub-channel processing functionality that is supported according to thepresent invention. A signal is received from a communication channel.The communication channel may be a wired (or wireline) or wirelesscommunication channel without departing from the scope and spirit of theinvention. The received signal undergoes receiver pre-processing thatmay include: performing tuning to a particular frequency band,performing carrier frequency recovery, digital sampling using an analogto digital converter (ADC), generating I,Q inputs from a receivedsampled signal, and generating a stream of soft symbol decisions. Thestream of soft symbol decisions is output from the receiverpre-processing functional block and is provided to a PHY sub-channelselection functional block. The selection of the sub-channels withinthis functional block may be performed as directed by a user (orsubscriber) that employs a receiver supporting the functionality of theFIG. 11. Alternatively, the selection of the sub-channels within thisfunctional block may be performed as directed by decoded informationthat is fed back from a forward error correction (FEC) processingfunctional block.

The selected sub-channel is provided to the FEC processing functionalblock from the PHY sub-channel selection functional block. The FECprocessing functional block performs the actual decoding of stream ofsoft symbol decisions provided by the receiver pre-processing functionalblock that have been selected and assigned to a sub-channel within thePHY sub-channel selection functional block. In embodiments where atraining field has been encoded and transmitted to a receiver, the FECprocessing functional block decoded this coded training field (CTF) foruse in decoding subsequent soft symbols within the stream of soft symboldecisions. The CTF may be coded to include a variety of different typesof information for use in decoding and processing subsequent softsymbols. Various embodiments of which types of information may beincluded therein are described in more detail below.

The output of the FEC processing functional block is a decoded bitstream that may be provided to any one of a variety of higher levelapplications. This decoded bit stream may be viewed as being the harddecisions that are generated from the soft symbol decisions that areoutput from the receiver pre-processing functional block. These are thebest estimates of the data that has been encoded and transmitted to thereceiver that supports the PHY sub-channel processing functionalityshown and described in the FIG. 11.

The PHY sub-channel selection functional block substantially reduces thetotal amount of data that the FEC processing functional block mustprocess and decode. In doing this, the PHY sub-channel selectionfunctional block selectively feeds data to the FEC processing functionalblock. Only the received data that is destined, or intended, for aparticular receiver then undergoes the full processing and decoding.Whereas in previous prior art implementations, all of the received datais processed and only at the higher levels is the fully decoded datadiscerned as whether it is intended for this particular receiver. ThePHY sub-channel selection functional block greatly reduces theprocessing of receives data by a receiver by enabling the selection ofthe data to be pushed back into the physical layer (PHY), rather thanbeing performed at a higher layer (such as at a medium access control(MAC) layer). It is noted that the invention also includes encoding theinformation n such a way that the data is encoded, at a transmitter endof a communication channel, into such a symbol sequence that data may beextracted using one or more of the PHY sub-channel processing techniquesdescribed herein.

FIG. 12 is a diagram illustrating an embodiment of a receiver arrangedto support PHY sub-channel processing 1200 according to the presentinvention. A signal is received from a communication channel. Thisreceived signal is provided to a demodulator that performs tuning,carrier frequency recovery, and employs a soft symbol generator togenerate a soft symbol decision stream from the received signal. Inaddition, the demodulator may be viewed as performing the necessaryfunctions to support the generation of the soft symbol decision stream,including performing digital sampling of the received signal, extractionof the I,Q components of the received signal, performing anydown-converting and filtering to get the received signal down to abaseband signal thereby being available for the PHY sub-channelprocessing of the invention.

The soft symbol decision stream is provided to a header processor. Theheader processor locates a training field within the soft decisionstream. In doing so, the header processor employs a correlator in oneembodiment. This correlator may be implemented using a pseudo-noise (PN)random sequence and a 128 tap filter. The correlator scans the softsymbol decision stream to locate the training field. Again, it is notedthat this training field, when coded to be a CTF, is decoded and thenidentified as being the training field.

The header processor also includes a soft symbol decision streamsub-channel parser that performs the functionality to select theappropriate soft symbols of the soft symbol decision stream that are tobe assigned and provided to a FEC correction processor via asub-channel. The soft symbol decision stream sub-channel parser enablesselective feeding of symbols of the soft symbol decision stream to theFEC correction processor. It is also noted that this embodiment allows asubscriber to direct the selection of the sub-channel made by the softsymbol decision stream sub-channel parser. Alternatively, informationextracted from a decoded CTF is fed back to the soft symbol decisionstream sub-channel parser, within the header processor, to direct theselection of a subsequent sub-channel to be provided to the FECcorrection processor.

The FEC correction processor performs the actual decoding of theselected symbols provided to it by the header processor via asub-channel. Only the soft symbol decisions within this sub-channel needbe decoded by the FEC processor. The FEC processor, in performing softsymbol decision decoding, generates the best estimate of the soft symboldecisions. This may be viewed as generating hard decisions correspondingto these soft symbol decisions. Again, when a CTF is provided to thereceiver that is arranged to include the functionality and components ofthe FIG. 12, then the CTF may be decoded in a similar way that data isdecoded. The information extracted from the CTF is then fed back to theheader processor to assist in the direction of decoding of subsequentsoft symbols of the received soft symbol decision stream.

The now decoded bit stream, provided from the FEC processor, may then beprovided to one or more higher level applications. For example, this bitstream may be provided for use in MPEG-2 transport processorapplications, DOCSIS (Data Over Cable Service Interface Specification)applications, display applications, medium access control (MAC)applications, . . . , and any number of other higher level applicationsas well.

The embodiment of the FIG. 12 shows yet another embodiment where PHYsub-channel processing may be achieved according to the invention. Ascan be seen, by performing the selective feeding of only the requiredportions of the received data to the FEC processor, a great deal ofunnecessary processing of data may be avoided altogether. The PHYsub-channel processing performs selection of the appropriate data to beprocessed by the FEC processor in the physical layer rather than in theMAC layer (or some other higher layer). This may result in greathardware and processing savings within a receiver that implements thePHY sub-channel processing shown in the FIG. 12.

FIG. 13 is a diagram illustrating an embodiment of PHY sub-channelprocessing that is performed according to the present invention. The topof the FIG. 13 shows an incoming soft symbol decision stream. This softsymbol decision stream, provided from a receiver pre-processingfunctional block, is provided to a header processor. The soft symboldecision stream includes a number of training fields interposed betweensymbol frames; in this embodiment, the training fields are not codedtraining fields (CTFs). Each of the symbol frames includes one or moresoft symbol blocks (SSBs). Each of the SSBs includes one or more actualsoft symbols, and each of the soft symbols is composed of one or moredigital bits. The invention is operable to support a variety of coderates that may be implemented using a variety of modulations(constellations and mappings) as will be described in variousembodiments below as well.

The same soft symbol decision stream may be generated within receiverpre-processing of a variety of receivers, shown in this embodiment as areceiver 1, . . . , and a receiver b. In the other embodiments describedherein that show only a single receiver embodiment, it is understoodthat multiple receivers may similarly be arranged to receive a commonbroadcast signal provided to the multiple receivers.

A header processor of receiver 1 receives the soft symbol decisionstream and selectively generates a sub-channel 1 and selectively feedsit to an FEC processor of the receiver 1. The FEC processor of thereceiver 1 then generates a decoded bit stream that corresponds to theSSBs that have been used to generate the sub-channel 1. The selection ofthese particular SSBs, to generate the sub-channel 1 for the receiver 1,is based on the selection provided to the header processor of thereceiver 1. This external direction to perform the selection may beprovided by a subscriber in this embodiment. To illustrate thefunctionality of the PHY sub-channel processing supported in thisembodiment, we may look at the selection of the SSBs from the softsymbol decision stream to generate the sub-channel 1 within the receiver1. The selection within the header processor of the receiver 1 selectsthe first SSB following a training field within each frame. Theseselected first SSBs of each frame of the soft symbol decision stream arethen provided to the FEC processor of the receiver 1 as a sub-channel 1.This represents only a portion of the total received data within thesoft symbol decision stream. However, this selection of only a portionof the soft symbol decision stream, specifically a selection of onlysome of the SSBs contained therein, substantially reduces the totalprocessing to be performed by the FEC processor of the receiver 1.

The operation of the receiver b is also shown to illustrate how theselection of SSBs from the soft symbol decision stream may be made whena header processor of another receiver is directed to select another SSBfrom each of the frames of the soft symbol decision stream. In thisembodiment shown in the FIG. 13, the header processor of the receiver bselects the third SSB from each frame and uses those SSBs to genera asub-channel 3 to be processed by a FEC processor of the receiver b.

The operation within the FIG. 13 shows how each of the SSBs within thevarious frames of the soft symbol decision stream may be associated witha sub-channel. For example, the first SSB of each frame may be used togenerate a sub-channel 1; the second SSB of each frame may be used togenerate a sub-channel 2; . . . ; and (in general) the nth SSB of eachframe may be used to generate a sub-channel n. This embodiment shows howthere may be n SSBs within each frame of the soft symbol decisionstream. In performing the PHY sub-channel processing according to theinvention, only those SSBs containing information that is requested by aparticular receiver need to be decoded. The non-selected SSBs of theframes may be discarded and unused until the selection of the receiveris changed.

For example, at one instant in time, the receiver 1 may select theinformation contained within the first SSBs of the frames of the softsymbol decision stream. Then, at a later instant in time, the receiver 1may then select the information contained within the third SSBs of theframes of the soft symbol decision stream. In such a case, the headerprocessor of the receiver 1 would then switch its selection of the thirdSSBs of the frames of the soft symbol decision stream thereby generatingthe sub-channel 3.

FIG. 14 is a diagram illustrating another embodiment of PHY sub-channelprocessing that is performed according to the present invention. The topof the FIG. 14 shows an incoming soft symbol decision stream. This softsymbol decision stream, provided from a receiver pre-processingfunctional block, is provided to a header processor. The soft symboldecision stream includes a number of coded training fields (CTFs)interposed between symbol frames. Each of the symbol frames includes oneor more soft symbol blocks (SSBs). Each of the SSBs includes one or moreactual soft symbols, and each of the soft symbols is composed of one ormore digital bits. The invention is operable to support a variety ofcode rates that may be implemented using a variety of modulations(constellations and mappings) as will be described in variousembodiments below as well.

The FIG. 14 shows how a header processor of a receiver may selectivelyand dynamically change the selection of the SSB to be selected fromvarious frames of a soft symbol decision stream when performing decodingof data contained within the soft symbol decision stream.

For example, an FEC processor of the receiver decoded a CTF 0 to extractthe information contained therein. This information is then fed back tothe header processor of the receiver to direct the selection of the SSBof a subsequent frame of the soft symbol decision stream. In addition,the CTFs may also include additional information that may be employed todirect the decoding of subsequent SSBs of the soft symbol decisionstream.

In one embodiment, the information extracted from the CTF 0 s used todirect the selection of the SSB from the following frame of the softsymbol decision stream. In the embodiment of the FIG. 13, theinformation extract from the CTF 0 is used to direct the headerprocessor to select the SSB 1,1 from the frame 1. Then, after the FECprocessor of the receiver decodes the CTF 1 that follows the frame 1,the information extracted there from is used to direct the headerprocessor to select the SSB 3,2 from the frame 2 (or the third SSBwithin the frame 2). Continuing on, after the FEC processor of thereceiver decodes the CTF 2 that follows the frame 2, the informationextracted there from is used to direct the header processor to selectthe SSB 2,3 from the frame 3 (or the second SSB within the frame 3).This header processor may continue on to enable the dynamic selection ofthe appropriate SSB from subsequent frames within the soft symboldecision stream based on information extracted from the CTFs.

The look ahead of the selection may also be variable, for example, a CTFmay include information directing how to select the appropriate SSB fromthe very next frame of the soft symbol decision stream; alternatively,the a CTF may include information directing how to select theappropriate SSB from the 2^(nd) next frame of the soft symbol decisionstream, or the appropriate SSB from the nth next frame. This embodimentif illustrated in more detail on the FIG. 15.

FIG. 15 is a diagram illustrating an embodiment of information codedwithin soft symbol blocks of a sub-channel and programmable look aheadto subsequent frames according to the invention. A soft symbol decisionstream including a number of CTFs interposed between frames of SSBs isreceived. Each of the CTFs may include one or more of the following:information to be decoded to direct selection of subsequent SSBs (togenerate subsequent sub-channels), the framing structure of the SSBs(that governs the number of SSBs per frame, etc.), and/or information ofmodulation (constellation and mapping) of the individual symbols of theSSBs. This modulation information may be used to support decoding ofsymbols coding using various code rates. The modulation information maybe extracted to direct an FEC processor to employ the appropriatemodulation (constellation and mapping) when performing the decoding.

As shown in the FIG. 15, the look ahead may be variable. For example,the information extracted from the CTF 0 may be associated with frame 1,with frame 2, and/or with frame 3. There may be a number of reasonswhere the look ahead may be vary including the processing speed andcapability of the receiver. As an example, when a receiver hassufficient speed to process a CTF and employ the extracted informationcontained therein to direct the processing of the very next frame, thenthe information within the CTF 0 may be used to direct the selection anddecoding of the SSBs within the frame 1. However, when the receiver isunable to extract the information from a CTF and feed that informationback to a header processor to direct the selection and decoding of thevery next frame of a soft symbol decision stream, then the look aheadmay apply this information to subsequent frames.

FIG. 16 is a diagram illustrating an embodiment of information codedwithin soft symbol blocks of a sub-channel according to the invention.The FIG. 16 shows a particular embodiment of how information containedwithin CTFs may be used to direct the decoding of the immediatelyfollowing frames that each contains four SSBs. Clearly, this may also beextendible to direct the decoding of the frames that follow even furtherdown the soft symbol decision stream as well. However, this embodimentshows how the information coded within a CTF is associated with afollowing frame to illustrate this aspect of the PHY sub-channelprocessing in general. This embodiment shows how the information isassociated with how to decode the individual SSBs within the frame. Theselection of which SSB to use to generate a sub-channel may be performedusing any of the various embodiments described herein. In addition, isit also noted that the information extracted from the CTF may alsoinclude information of how to decode the individual symbols of the SSBswithin the frames of the soft symbol decision stream. For example,different soft symbols within an SSB may have each been coded using adifferent code rate.

The CTF 0 includes information of how to decode each of the SSBs withinthe frame 1. In this embodiment, the SSB 1,1 of the frame 1 is to bedecoded using a code rate 1. Similarly, the SSB 2,1 of the frame 1 is tobe decoded using a code rate 4; the SSB 3,1 of the frame 1 is to bedecoded using a code rate 12; and the SSB 4,1 of the frame 1 is to bedecoded using a code rate 9. The code rates direct which modulation(constellation and mapping) is to be used to decode one or more of thesymbols within the SSB.

Similarly, the CTF 1 includes information of how to decode each of theSSBs within the frame 2. In this embodiment, the SSB 1,2 of the frame 2is to be decoded using a code rate 9. Similarly, the SSB 2,2 of theframe 2 is to be decoded using a code rate 8; the SSB 3,2 of the frame 2is to be decoded using a code rate 2; and the SSB 4,2 of the frame 2 isto be decoded using a code rate 3. Again, the code rates direct whichmodulation (constellation and mapping) is to be used to decode one ormore of the symbols within the SSB.

FIG. 17 is a diagram illustrating an embodiment of code rates that areemployed to decode soft symbol blocks of sub-channels according to theinvention. Each code rate is associated with a modulation that has aconstellation and a mapping for that constellation; this relationshipmay be ascertained when following through the FIG. 17. The FIG. 17 showshow a code rate invokes a modulation (selected from a number ofmodulations) and how each of the modulations is associated with aconstellation and a mapping. As the SSBs of a soft symbol decisionstream are provided via a sub-channel, they are then matched up with anappropriate code rate. Therein, the code rate directs which modulation(constellation and mapping) are to be used to decode the symbolscontained therein. Again, is it noted that the code rate may directdifferent symbols within the SSB to be decoded using differentmodulations (constellations and mappings) as well. By employing theappropriate modulations (constellations and mappings) to the symbolswithin an SSB, then properly decoded SSBs of the sub-channel may begenerated.

Looking at one example within the FIG. 17, looking at the code rate ofthe FIG. 17, a modulation #1 is selected from a number of availablemodulations. This modulation #1 corresponds to a constellation #2,selected from a number of available constellations, and a mapping #z ofthe constellation #2. It is noted that a single constellation type mayemploy different mappings in different code rates.

There are a variety of constellation types employed by modulations asknown in the art, and the invention is extendible to any of these. Somemodulation examples include BPSK (Binary Phase Shift Keying), QPSK(Quadrature Phase Shift Keying), PSK (Phase Shift Keying), QAM(Quadrature Amplitude Modulation), APSK (Amplitude Phase Shift Keying),and variants thereof including 8 PSK, and higher orders of PSK, 16 QAM,and higher orders of QAM, among other types of modulations.

FIG. 18 is a diagram illustrating an embodiment of code rates employedto decode soft symbol blocks according to the invention. The FIG. 18shows a specific embodiment of the FIG. 17. We look at two differentcode rates, code rate 1 and code rate n, and determine which modulation(constellation and mapping) each of them are to use when decoding asymbol.

We will look at two different code rates that each employs 8 PSK typeconstellations. Looking first at the code rate 1, the modulation #1 isselected from a number of available modulations. The modulation #1 isassociated with an 8 PSK type constellation, and the code rate 1 employsa mapping #1 of its 8 PSK type constellation. Looking at the code raten, which also employs an 8 PSK type constellation, the modulation #2 isselected, the 8 PSK constellation type is selected, and a mapping #n ofits 8 PSK type constellation is employed. For an even clearunderstanding of this functionality, we look now to FIG. 19 that showssome possible mappings to be employed by the code rate 1 and n.

FIG. 19 is a constellation diagram illustrating an embodiment ofmodulations (constellations and mappings) for code rates 1 and n shownin FIG. 18. The FIG. 19 shows 8 PSK type constellations that may beemployed according to the invention. Each of the constellation pointswithin these two constellations has different amplitudes. However,identical constellations may be used without departing from the scopeand spirit of the invention as well (when all of the constellations forcode rate 1 and code rate n have the same magnitude). The FIG. 19 showshow the 3 bit symbols, employed within 8 PSK, may be used to providedifferent mappings to constellation points located in the same generalvicinity of the I,Q plane. This embodiment of employing 8 PSK is shownhere specifically, yet it is understood that other code rates, perhapsemploying different modulations (constellations and mappings) maysimilarly be used according to the invention.

FIG. 20 is a diagram illustrating an embodiment of PHY sub-channelselection of a video broadcast signal according to the invention. Asingle broadcast signal is received by a PHY sub-channel selectionfunctional block. In this embodiment, the broadcast signal includesvideo information for channels 1-24 that may be extracted and playedback by a user. The PHY sub-channel selection functional block parsesthe received broadcast signal into a number of sub-channels. The firstSSB (SSB 1) of each frame is used to generate the sub-channel thatcarries the information contained within the video channels 1-6 of thebroadcast signal; this sub-channel may be viewed as being a group ofinformation channels. In this situation, these information channels arevideo information channels. The second SSB (SSB 2) of each frame is usedto generate the sub-channel that carries the information containedwithin the video channels 7-12 of the broadcast signal. Similarly, thethird SSB (SSB 3) of each frame is used to generate the sub-channel thatcarries the information contained within the video channels 13-18 of thebroadcast signal; and fourth SSB (SSB 4) of each frame is used togenerate the sub-channel that carries the information contained withinthe video channels 19-24 of the broadcast signal.

Again, each of the sub-channels that carry the video information of thevideo channels 1-6, 7-12, 13-18, and 19-24, respectively, may be viewedas containing a group of information channels. Clearly, the inventiveconcept of partitioning of a broadcast video signal into a number ofsub-channels, where each sub-channel may include a number of videoinformation channels, may also be extended to media beyond only videosignals. As one example, an audio signal may similarly be partitionedinto a number of sub-channel where each sub-channel may include a numberof audio information channels contained therein.

The FIG. 20 shows how a multitude of information may still be carried oneach of the sub-channels according to the invention. However, theparsing performed by the PHY sub-channel selection functional blockgreatly reduces the total amount of information that needs to beprocessed to extract the information for, say, channel 1. Rather thantuning to and decoding the entire broadcast signal, and then filteringout only the selected information corresponding to the channel 1, thetuning need only be performed on the sub-channel 1. In this embodiment,there is a reduction of processing by a factor of 4. The sub-channel 1,including the first SSB (SSB 1) of each frame and information containedwithin the channels 1-6 of the broadcast signal), may then be decodedand filtered to extract the information contained within the channel 1.

The FIG. 20 is shown specifically in the context of a video broadcastsignal application; however, the PHY sub-channel processing is clearlyextendible to other signal types as well including data and audio, amongother signal types.

FIG. 21 is an operational flow diagram illustrating an embodiment of asub-channel processing method 2100 that is performed according to thepresent invention. In a block 2120, a signal is received from acommunication channel. In a block 2120, a soft symbol decision stream isgenerated from the received signal. In a block 2130, the soft symboldecision stream is parsed into one or more sub-channels. This parsingmay be directed as being performed by user selection, as shown in ablock 2132.

Then, as shown in a block 2140, FEC decoding is performed on the softsymbol decisions of the sub-channel to generate a decoded bit stream. Ina block 2150, this decoded bit stream may then be provided to one ormore higher level applications.

FIG. 22 is an operational flow diagram illustrating another embodimentof a sub-channel processing method 2200 that is performed according tothe present invention. In a block 2210, a soft symbol decision stream isreceived. As shown in a block 2220, a coded training field (CTF) islocated within the soft symbol decision stream. Within a block 2230, afirst block of a first frame of the soft symbol decision stream isassigned into a first sub-channel using a predetermined assignmentapproach. FEC decoding is performed on the CTF, in a block 2240, toextract coded information contained therein. In a block 2250, FECdecoding is performed on the first sub-channel using a predeterminedcode rate.

After the CTF has been decoded and the information contained therein isavailable for use in assigning subsequent SSBs (of subsequent frames)into sub-channels and in decoding the subsequent SSBs of thosesubsequent frames. In a block 2260, the extracted coded information isemployed to direct assigning of a second SSB of second frame of the softsymbol decision stream into a second sub-channel. In addition, in ablock 2270, the extracted coded information is employed to direct FECdecoding of the second SSB of a second frame of the soft symbol decisionstream into a second sub-channel.

In view of the above detailed description of the invention andassociated drawings, other modifications and variations will now becomeapparent. It should also be apparent that such other modifications andvariations may be effected without departing from the spirit and scopeof the invention.

1. A communication device, comprising: a processor that is operable to: receive a sequence that includes a plurality of coded training fields interspersed among a plurality of frames; decode a first coded training field thereby extracting a first plurality of parameters; decode a first frame of the plurality of frames, that is subsequent to the first coded training field within the received sequence, using the first plurality of parameters thereby generating a first decoded bit; decode a second coded training field thereby extracting a second plurality of parameters; and decode a second frame of the plurality of frames, that is subsequent to the second coded training field within the received sequence, using the second plurality of parameters thereby generating a second decoded bit; and wherein: the first plurality of parameters includes at least one of a first code rate and a first modulation indicating a first constellation having a corresponding first mapping by which at least one symbol within the first frame is to be decoded; and the second plurality of parameters includes at least one of a second code rate and a second modulation indicating a second constellation having a corresponding second mapping by which at least one symbol within the second frame is to be decoded.
 2. The communication device of claim 1, wherein: the first coded training field is followed by the first frame; the first frame is followed by the second coded training field; and the second coded training field is followed by the second frame.
 3. The communication device of claim 1, wherein: the first coded training field is followed by the first frame; and at least one additional frame is interposed between the first coded training field and the first frame.
 4. The communication device of claim 1, wherein: the first plurality of parameters includes the first modulation indicating the first constellation having the corresponding first mapping by which a first symbol within the first frame is to be decoded; and the first plurality of parameters includes a third modulation indicating a third constellation having a corresponding third mapping by which a second symbol within the first frame is to be decoded.
 5. The communication device of claim 1, wherein: the first plurality of parameters includes the first modulation indicating the first constellation having the corresponding first mapping by which a first symbol within the first frame is to be decoded; and the first plurality of parameters includes a third modulation indicating the first constellation having a corresponding third mapping by which a second symbol within the first frame is to be decoded.
 6. The communication device of claim 1, wherein: the first plurality of parameters includes the first code rate by which a first symbol within the first frame is to be decoded; and the first plurality of parameters includes a third code rate by which a second symbol within the first frame is to be decoded.
 7. The communication device of claim 1, further comprising: a demodulator that is operable to: receive a signal from a communication channel; and process the received signal thereby generating a plurality of soft symbol decisions; and wherein: the sequence received by the processor includes selected soft symbol decisions within the plurality of soft symbol decisions.
 8. The communication device of claim 1, further comprising: a demodulator that is operable to: receive a signal from a communication channel; and process the received signal thereby generating a first plurality of soft symbol decisions corresponding to a first sub-channel and a second plurality of soft symbol decisions corresponding to a second sub-channel; and a header processor that is operable to select the first plurality of soft symbol decisions or the second plurality of soft symbol decisions thereby generating the sequence that is received by the processor.
 9. The communication device of claim 1, wherein: at least one of the first modulation and the second modulation is Amplitude Phase Shift Keying (APSK), Quadrature Phase Shift Keying (QPSK), 8 Phase Shift Keying (PSK), 16 Quadrature Amplitude Modulation (QAM), or 16 Amplitude Phase Shift Keying (APSK).
 10. The communication device of claim 1, wherein: the communication device is a satellite receiver, a high definition television (HDTV) set top box receiver, a mobile receiver, a base station receiver, a mobile unit, a receiver, or a transceiver.
 11. A communication device, comprising: a header processor that is operable to process a soft symbol stream thereby generating a sequence that includes a plurality of coded training fields interspersed among a plurality of frames; a forward error correction processor that is operable to: receive the sequence that includes the plurality of coded training fields interspersed among the plurality of frames; decode a first coded training field thereby extracting a first plurality of parameters; decode a first frame of the plurality of frames, that is subsequent to the first coded training field within the received sequence, using the first plurality of parameters thereby generating a first decoded bit; decode a second coded training field thereby extracting a second plurality of parameters; and decode a second frame of the plurality of frames, that is subsequent to the second coded training field within the received sequence, using the second plurality of parameters thereby generating a second decoded bit; and wherein: the first plurality of parameters includes at least one of a first code rate and a first modulation indicating a first constellation having a corresponding first mapping by which at least one symbol within the first frame is to be decoded; and the second plurality of parameters includes at least one of a second code rate and a second modulation indicating a second constellation having a corresponding second mapping by which at least one symbol within the second frame is to be decoded.
 12. The communication device of claim 11, wherein: the header processor is operable to select a first plurality of soft symbol decisions or a second plurality of soft symbol decisions from the soft symbol stream thereby generating the sequence that includes the plurality of coded training fields interspersed among the plurality of frames.
 13. The communication device of claim 11, wherein: the first coded training field is followed by the first frame; the first frame is followed by the second coded training field; and the second coded training field is followed by the second frame.
 14. The communication device of claim 11, wherein: the first coded training field is followed by the first frame; and at least one additional frame is interposed between the first coded training field and the first frame.
 15. The communication device of claim 11, wherein: the first plurality of parameters includes the first modulation indicating the first constellation having the corresponding first mapping by which a first symbol within the first frame is to be decoded; and the first plurality of parameters includes a third modulation indicating a third constellation having a corresponding third mapping by which a second symbol within the first frame is to be decoded.
 16. The communication device of claim 11, wherein: the first plurality of parameters includes the first code rate by which a first symbol within the first frame is to be decoded; and the first plurality of parameters includes a third code rate by which a second symbol within the first frame is to be decoded.
 17. The communication device of claim 11, wherein: the communication device is a satellite receiver, a high definition television (HDTV) set top box receiver, a mobile receiver, a base station receiver, a mobile unit, a receiver, or a transceiver.
 18. A method, comprising: receiving a sequence that includes a plurality of coded training fields interspersed among a plurality of frames; decoding a first coded training field thereby extracting a first plurality of parameters; decoding a first frame of the plurality of frames, that is subsequent to the first coded training field within the received sequence, using the first plurality of parameters thereby generating a first decoded bit; decoding a second coded training field thereby extracting a second plurality of parameters; and decoding a second frame of the plurality of frames, that is subsequent to the second coded training field within the received sequence, using the second plurality of parameters thereby generating a second decoded bit; and wherein: the first plurality of parameters includes at least one of a first code rate and a first modulation indicating a first constellation having a corresponding first mapping by which at least one symbol within the first frame is to be decoded; and the second plurality of parameters includes at least one of a second code rate and a second modulation indicating a second constellation having a corresponding second mapping by which at least one symbol within the second frame is to be decoded.
 19. The method of claim 18, wherein: the first plurality of parameters includes the first code rate and the first modulation indicating the first constellation having the corresponding first mapping by which a first symbol within the first frame is to be decoded; and the first plurality of parameters includes a third code rate and a third modulation indicating a third constellation having a corresponding third mapping by which a second symbol within the first frame is to be decoded.
 20. The method of claim 18, wherein: the method is performed within a communication device; and the communication device is a satellite receiver, a high definition television (HDTV) set top box receiver, a mobile receiver, a base station receiver, a mobile unit, a receiver, or a transceiver. 